Analog Devices Inc. ADL5371-EVALZ

Overview

ADL5371-EVALZ from Analog Devices is a Pb-free evaluation board designed to characterize the ADL5371 fixed-gain quadrature modulator - a 500 MHz to 1500 MHz RF IC that accepts differential baseband I/Q inputs and a single-ended LO to generate a single-ended RF output. It delivers 7.6 dBm typical SSB output power, −55 dBc sideband suppression, and −50 dBm carrier feedthrough at 900 MHz, enabling high-performance zero-IF or low-IF transmitter design in cellular and broadband wireless systems.

For engineers reviewing the ADL5371-EVALZ datasheet, ADL5371-EVALZ setup guide, ADL5371-EVALZ test configuration, or ADL5371-EVALZ compatibility with AD9779 DACs, this board provides full access to all 24 LFCSP pins of the ADL5371 modulator, on-board 0.1 µF bypass capacitors, ac-coupling for LO and RF paths, and ground-plane optimized layout per AN-772 - supporting rapid validation of modulation linearity, noise floor, and nulling performance across temperature and frequency.

Technical Context

The ADL5371-EVALZ implements the complete signal chain for the ADL5371 modulator: single-ended LO input (LOIP/LOIN) feeds a polyphase quadrature splitter and limiting amplifier; differential baseband inputs (IBBP/IBBN/QBBP/QBBN) interface via 50 Ω bias resistors to establish 500 mV dc common-mode; and the internal balun delivers single-ended RF output (VOUT) with 50 Ω source impedance requiring external matching per S22 data.

Board-level design enforces strict grounding: COM1–COM4 pins and exposed paddle connect to a multi-layer ground plane stitched with nine vias; all five VPS supply groups (VPS1–VPS5) are decoupled with 0.1 µF capacitors placed adjacent to respective pins; and baseband filtering options (e.g., third-order elliptical LPF at 3 MHz) are supported via optional component footprints per Figure 30 of the datasheet.

Key Specifications

Availability

ADL5371-EVALZ is available at Aetrix Electronics and suitable for RF transceiver development, cellular base station prototyping, and broadband wireless access system validation requiring stable component supply and traceable evaluation hardware.

Supply support for ADL5371-EVALZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide and ISO 9001-certified manufacturing.

The ADL5371-EVALZ belongs to Analog Devices' RF & Microwave Evaluation Platform product line, engineered specifically to accelerate characterization and integration of high-linearity quadrature modulators in 5G infrastructure, WiMAX, and satellite modem applications.

FAQ

What is the primary function of the ADL5371-EVALZ?

The ADL5371-EVALZ is a dedicated evaluation board for the ADL5371 fixed-gain quadrature modulator. It provides full electrical access to all 24 pins of the ADL5371 in its 24-lead LFCSP package, implements recommended decoupling (0.1 µF per VPS group), ac-couples LO and RF paths, and supports baseband biasing and filtering per Analog Devices' application guidance. It does not contain active circuitry beyond passive interface components - its sole purpose is accurate, repeatable characterization of the ADL5371 modulator's RF performance.

Does ADL5371-EVALZ support both differential and single-ended baseband inputs?

No - the ADL5371-EVALZ is configured exclusively for differential baseband drive as required by the ADL5371. The board provides four dedicated terminals (IBBP, IBBN, QBBP, QBBN) with 50 Ω resistors to ground to establish the mandatory 500 mV dc common-mode bias. It does not support single-ended baseband input; attempting such a connection would violate the ADL5371's input architecture and degrade quadrature accuracy, carrier feedthrough, and sideband suppression.

Can ADL5371-EVALZ be used with LO sources other than 0 dBm?

Yes - the ADL5371-EVALZ accommodates LO drive levels from −6 dBm to +6 dBm per the ADL5371's Absolute Maximum Ratings and characterization data. While 0 dBm is the nominal recommended level, increasing LO power up to +6 dBm improves noise floor (e.g., −158.5 dBc/Hz in GSM) at the cost of reduced sideband suppression. The board's LOIP/LOIN interface remains valid across this range; no hardware modification is needed, but users must verify LO source impedance and ac-coupling capacitor rating for higher-power operation.

How is carrier feedthrough nulling implemented on ADL5371-EVALZ?

The ADL5371-EVALZ itself does not include active nulling circuitry. However, it provides unobstructed access to all baseband input pins (IBBP/IBBN/QBBP/QBBN) and ground reference points (COM1–COM4), enabling external dc offset injection - for example, using the AD9779's auxiliary DACs with precision resistors (Figure 31) or bench instrumentation. Nulling is performed iteratively: first adjust Q-channel offset to minimize carrier feedthrough, then fine-tune I-channel offset, repeating until residual falls near the noise floor (−158.6 dBm/Hz).

Is the ADL5371-EVALZ RoHS-compliant and Pb-free?

Yes - the ADL5371-EVALZ is explicitly described in the datasheet as a "Pb-free evaluation board" and conforms to RoHS Directive 2011/65/EU. Its PCB uses lead-free solder, and all onboard passives (capacitors, resistors) and connectors meet JEDEC J-STD-609A Class 1 moisture sensitivity and halogen-free requirements. No leaded components are present, and the board ships with full compliance documentation traceable to Analog Devices' material declarations.